1. Technical Field
The present invention relates to a jet aircraft configuration. More particularly, the present invention provides an improved aircraft which is quickly reconfigurable from a cargo or passenger configuration into one adapted for parabolic flight operations (zero-gravity) for entertainment purposes.
2. Related Information
The National Aeronautics and Space Administration (NASA) has for many years conducted so-called parabolic flights in order to simulate zero-gravity situations. NASA developed a KC-135 jet aircraft specifically adapted for flying such missions. Parabolic flights are used, for example, to train astronauts in realistic outer space scenarios. In a parabolic flight pattern, the aircraft starts at about 28,000 feet and begins a descent using a flight path which creates a zero-gravity condition on the airplane.
The aircraft requires special modifications to support a zero-gravity condition. As one example, hydraulic systems must be modified to prevent hydraulic fluid from "cavitating" during low-gravity periods. These and other modifications are described in a prior art NASA document entitled "KC-135 Modifications Manual", dated Apr. 5, 1982, incorporated herein by reference.
Recently, the concept of using parabolic (zero-gravity) flights for entertainment purposes has been proposed. For example, paying customers would be initially strapped into seats during take-off, and then would be free to float about the cabin during the zero-gravity period, which typically lasts about 30 seconds per dive.
In contrast to the NASA KC-135 modifications, there are many problems associated with providing zero-gravity flights for commercial entertainment purposes. For example, whereas NASA is generally exempted from various safety standards and comfort requirements, a commercial parabolic flight aircraft must meet such requirements. Moreover, using a dedicated aircraft for entertainment purposes is prohibitively expensive. Normal turbojet aircraft operations can be extremely expensive, running on the order of $20,000-$30,000 per day. Because parabolic flights are inherently conducted over short periods of time each day, use of a dedicated aircraft for parabolic flight operations, as done by NASA, is cost prohibitive for entertainment purposes.
In addition, because NASA's parabolic aircraft is flown under public aircraft regulations, NASA is not monitored by the Federal Aviation Administration (FAA) and is not subject to the rigorous inspection and engineering design called out in the Federal Aviation Regulations (FARs). This set of regulations defines requirements that must be met in order to achieve a certificate for operation enabling an individual or organization to hold out to the general public. However, since no FAA specification exists specifically for parabolic flight operation, there are no clear set of design guidelines for providing a commercial passenger aircraft which meets all known FAA regulations for parabolic flights.